Week 3: how the elements are formed part 3 Flashcards
creator of cyclotron
Ernest O. Lawrence
proved that when an alpha particle from radium strikes a nitrogen atom, either a proton or a hydrogen nucleus is ejected
Ernest Rutherford
had the idea of electron orbits
Dane Niels Bohr
isolated polonium and radium
Marie Curie and Pierre Curie
discovered x-rays
W.K. Roentgen
discovered something he called a “spontaneous emission of penetrating rays from certain salts of uranium”;
H.A. Becquerel
the fifth “ essence “ by the greeks
ether
introduced the three alchemical symbols salt, sulfur, and mercury
paracelsus
The first discovery of a true element in historical time was that of phosphorus by whom?
Dr. Brand of Hamburg
Who made chlorine in 1774 by the action of “black manganese” (manganese dioxide) on concentrated muriatic acid (hydrochloric acid), but it was not recognized as an element till the work of Davy in 1810
Scheele
discovered aluminum, barium, boron, calcium, magnesium, potassium, sodium, and strontium.
Davy
invented the spectroscope
Bunsen and Kirchhoff
Compounds of these new elements were obtained by
by patient fractional recrystallization of their salts
isotopes were discovered by
Rutherford and Soddy
the 3 simplifications of all the external world or the elements
- Dobereiner’s Triads
- Newland’s law of octaves
- Mendeleev’s periodic law
discovered a method of transmuting one element into another
Rutherford
The most common way to artificially transform one element into another
by bombarding nuclei with nuclear projectiles
he first device capable of accelerating positive ions to the very high energies needed. Its basic principle of operation is not difficult to understand.
Ernest O. Lawrence’s cyclotron
a modern offspring of the first cyclotron, accelerates protons to 99.13% the speed of light, thereby giving them 6.2billion electron volts (BeV).
The bevatron
accelerates ions as heavy as neon to about 15% the speed of light.
heavy-ion linear accelerator
discovered the neutron.
James Chadwick
the element first made by artificial technical methods.
technetium
made for the first time from the fission disintegration products of uranium in the Clinton (Oak Ridge) reactor.
uranium
all other elements having a nuclear charge number greater than 84 are all what?
unstable
first made at Berkeley by bombarding bismuth with alpha particles, which produced astatine and released two neutrons.
astatine
this element was identified in 1939 by French scientist Marguerite Perey.
francium
the atom had split into two roughly equal pieces, together with some excess neutrons.
nuclear fission
brought back Democritus’ ancient idea of the atom.
John Dalton
1/3 of the basic ideas of Dalton’s atomic theory
All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles, created, or destroyed.
2/3 of the basic ideas of Dalton’s atomic theory
All atoms of the same element are alike and have the same mass. Atoms of different elements are different and have different masses.
3/3 of the basic ideas of Dalton’s atomic theory
Atoms join together to form compounds, and a given compound always consists of the same kinds of atoms in the same proportions.
